Sheet metal composition material



States 2,798,833 Patented July 9, 1957 SHEET METAL CGMPOSITION MATERIALLewis Lapsensohu, Erooidyn, Richard Lapsensolm, Glen Oaks, and JacobLapsensohn, Brooklyn, N. 51.; said Richard Lapsensohn and said JacobLapsensnhn assignors to said Lewis Lapsensolm No Drawing. AppiicationFebruary 25, 1954, Serial No. 412,662

6 Qlaims. (Cl. l54---45.9)

This invention relates to an improved article of manufacture, andparticularly to an improved sheet metal composition adaptable as aroofing and flashing material.

Composition materials for roofings and flashings have been known andused for many years. The very first material of this type to appear onthe market consisted of a metallic sheet or veneer to which was appliedan asphalt-coated felt. The metal veneer was applied while hot so as tocause it to adhere more securely to the coated felt. The material didnot receive a wide commercial acceptance because the asphalt layer incontact with the metal cracked and was readily broken loose by suddenshock. From the manufacturing point of View, it had the disadvantage inthat the metallic sheet or veneer had to be heated and pressed firmly tothe asphalt-coated felt. Realizing the shortcoming of this material, theroofing industry experimented with various bituminous masticcompositions which would serve as a binder or adhesive and which wouldbe nonflowing, non-cracking, and practically non-water absorptive. Thebituminous mastic was obtained by heating a mixture of heavywater-gas-tar and powdered bituminous coal in a still at a temperatureranging between 300 and 350 C. for a period of time of about /2 hours.The temperature was maintained for several hours, the heatingdiscontinued and the mixture allowed to cool. Within one hour after thetemperature slowly dropped, additional water-gas-tar-heavy oil wasstirred into the heat-treated coal and tar mass. The resulting productwas discharged from the still and constituted the binding material. Tothe latter, sand, clay, fibers, either mineral or vegetable, i. e.asbestos cotton, hair, etc. were added. As an alternative, the fibrousmaterial was precoated with the binding material, or other pitch tar, orhigh boiling tar distillate. The resulting mastic containingcoal-digestion pitch was directly bonded to the metal surface by heatand pressure. The bituminous mastic coated metal sheet did not provesuccessful because of certain disadvantages. The first was that when thecoated metal sheet was exposed to the suns rays, especially during thehot summer months, the mastic became loose and detached itself from thesupporting metal sheet. In other words, materials of this type wereunable to withstand the heat of the sun especially when utilized roofingmaterials or flashings.

To overcome the shortcomings of the bituminous mastic coated metalsheet, the industry conducted further experiments with the thought ofdecreasing or eliminating the detachability of the mastic material fromthe metal sheet. To achieve this objective it was thought that if to anasphalt mastic composition, containing a bulk-forming filler, asufiicient quantity of lime were added and the mixture heated, the limewould interact with the moisture and asphalt and cause the surfaceportion in contact with the metal to harden. In other words, if themixture containing the lime were applied to a sheet metal and heated,the heating process in presence of the lime would render the asphaltinert so that subsequent reheating to the same temperature would renderthe asphalt non-fluid and thereby avoid detachment or release of themastic layer from the metal sheet. This expedient did not provecommercially practicable because of the heat-treatment involved. Inaddition, when exposed to the hot sun-rays of the summer months, theasphaltic mastic composition still detached itself from the supportingsheet metal because of the fluidization of the asphalt material.

To overcome the above shortcoming, attempts were made to flex or crinklethe sheet metal coated material after the heating treatment. This,however, did not prove practical due to the fact that metal foils have adifferent coefiicient of expansion from that of the asphalt coatingbase, hence when such material was exposed to heat the metal foil becameruptured, loosened or detached from the asphalt base.

Another method used was to subject a metal foil coated with an asphaltbase over which was applied an asphalted felt to a set of rollers whichwould form wrinkles or ridges followed by longitudinal flexing of thefoil coated base to form transverse wrinkles or ridges. This expedientdid not solve the problem of preventing the asphaltic coat or adhesivelayer from detaching itself from the supporting metal sheet duringexposure to the suns rays.

Despite these various attempts to provide an improved product, thebuilding material industry reverted to the manufacture of thecomposition material of the asphaltcoated type applied to a metal sheetor veneer. This material is still unsatisfactory because of the sludgingand separation of the asphaltic layer or adhesive between the asphaltedfelt and sheet metal or veneer when the asphalted-felt side is appliedto a surface previously coated with a cut-back asphalt. It has beenfound that the lower boiling solvents in the cut-back asphalt penetrateor diffuse quite rapidly through the asphalted felt layer and come incontact with the asphalt layer. As a consequence thereof the layer tendsto sludge and gradually separate from the metal sheet or veneer. Inother words, the asphaltic layer begins to flow regardless whether themetal sheet or veneer is flat, corrugated, wrinkled or otherwise.

To provide a new sheet metal composition adaptable as a roofing andflashing material comprising a sheet metal or veneer bonded to a layerof a fibrous material free of all of the foregoing objections andshortcomings constitutes the principal object of the present invention.

Another object is to provide such composition in which there ispermanent adhesion between the sheet metal or veneer and fibrousmaterial.

A further object is to provide such composition in which the bondingagent is non-flowing, non-cracking and weather resistant.

A still further object is to provide such composition which retains itsunitary structure with extreme changes in temperature without rupture ordetachment of the sheet metal or veneer from the fibrous material.

Other objects and advantages will become apparent from the followingdescription.

In order to attain all of the foregoing objects, we have found that thebonding or adhesive layer to be employed between the sheet metal ormetal veneer and the fibrous material comprises a mixture of apolysulfide polymer and a resinous material selected from the classconsisting of epoxy ether resin, polyamide resin, resorcinolformaldehyde resin, cresolor alkylated phenolformaldehyde resin, andrelated phenolic resin of the A or B stages. Witheither one of thesemixtures, after curing, a bond or adhesive layer is obtained which will35 not flow at elevated temperatures, above 100 C., will not crack attemperatures as low as -65 F. and which has a high degree offlexibility, water and water vapor resistance, and resistance tosolvents; especially those utilized in cut-back asphalts.

The mixture of the bonding agent is'applied to one side of the sheetmetal or metal veneer by the usually employed coating machines to athickness ranging from .001 to A.; of an inch. The coating is applieddirectly while the sheet metal or metal veneer is travelling from a rollalong fixed rotating rollers. After the coating layer has been applied,a strip of self-supporting sheet of fibrous material having a thicknessof 0.001 to of an inch from an adjacent roll is applied directly to thecoated surface and immediately fed between two pressure rollers rotatingin the same direction to firmly press the fibrous material to thecoating. A short distance away from the two rollers a series ofinfra-red lamps may be placed so that as the fibrous material andcoating come in contact sufficient heat is given off to accelerate thecuring of the bonding or adhesive layer. This process is conventionaland is operated in a continuous manner. The application of heat isoptional, since the curing of the bonding layer takes place afterapplication and within one-half and one and one-half hours.

The sheet metal or metal veneer to be coated may be aluminum, copper,zinc, galvanized sheet metal, stainless steel, Monel metal and the like.In fact the constitution of the sheet metal is immaterial since anycommercially available sheet metal can be coated with the bonding agentsemployed herein. The thickness or gauge of the sheet metal may rangefrom .001 to of an inch.

The fibrous material may be of any type, such as, for example, cottonfabric, canvas, woven asbestos, glass fiber such as roving, matte andthe like, rag paper, kraft paper, asbestos paper, cardboard, or anynatural or synthetic fabric either alone or laminated with a glass fiberand the like may be used as such or impregnated with asphalt andemployed as the foundation base. Instead of these fibrous materialsasphalted-felt may be employed.

The asphalted-felt may be any one of the commercially availablematerials such as 10, 15, 60 or 90 1b. asphaltfelt. Of these, we preferto use the standard 15 lb. asphalt or coal tar pitch felt.

As an alternative, one surface of the sheet metal may be coated by meansof the conventional lithographic roller with any metal, paint, enamel,or commercially available metal surface coating containing syntheticresins such as epoxy ether esters or epoxy ethers modified with aurea-formaldehyde resin or a phenolic resin, and the like. Thesecoatings may contain dispersed copper, bronze, or aluminum powder orinorganic pigments normally used in outside paint and enamelformulations.

The sheet metal or veneer, after receiving the outside coating of paintor enamel, is passed along a roller to a baking oven having an internaltemperature of about 300-800 F. and kept there for about ].60 minutes.During this time the coating cures and dries to an insoluble infusiblestate. It is then Wound on a roller and employed for the coating of thebonding or adhesive layer.

The surface coated sheet metal or metal veneer prepared as above is thendirected on rollers to the coating machine for application of thebonding or adhesive agent and fibrous material, after which it is passedthrough the pressure rollers, and, if desired, passed further throughconventional rollers adapted to impress crimps, corrugations, orembossed designing.

The following are the components utilized in preparing the mixtures ofthe adhesive or bonding agent between the fibrous material and sheetmetal or metal veneer:

The polysulfide polymers, which constitute one component of the mixtureand which are mixed in the proportion of 25 to 100 parts by Weight per25 to 100 parts by weight of either polyamidc resin, epoxy ether resin,or any one of the commercially available phenolic resins 4 containing areactive methylol group, are characterized by the following formula:

wherein m represents a positive integer of from 3 to 23. These polymersare mobile liquids and have a molecular weight ranging from 500 toapproximately 4000. They are commercially available under the registeredtrademark Thiokol liquid polymers. The methods of their preparation arewell known to the art and need not be described herein.

Instead of the foregoing polysulfide polymers, we can also employpolyhydroxy polythio polymers disclosed in U. S. P. 2,527,375, and thepolythiopolymercaptans having a molecular weight of about 500 to 12,000which are mobile liquids at 25 C., prepared according to the methodsgiven in United States Patent 2,466,963. The disclosures of both ofthese patents are incorporated herein by reference, and referred tohereinafter and in the claims as polysulfide polymer.

We have found that 25 to parts by Weight of the above polysulfidepolymers, and 25 to 100 parts by weight of a polyamide resin formcompatible solutions with chlorobenzene, chloroform, cyclohexanol,methylene chloride or ethylene dichloride or mixtures thereof. When 50parts by Weight of the polysulfide polymer and 25 parts by weight ofpolyamide resin are dissolved at room temperature in 100 to parts byweight of the solvent or solvent mixture, a solution suitable for directcoating to the sheet metal, metal veneer or fibrous material isobtained. 3 to 6 parts by weight of any aliphatic or aromatic amine,preferably 2,4,6-tri(dimethylaminomethyl) phenol or diethylene triamine,or dimethylaminopropylamine may be added per 100 parts by weight of thesolvent-polymer-resin mixture to accelerate the curing reaction attemperatures varying between 20 and 75 C. Temperatures higher than 75 C.may be employed, if desired, to accelerate the evaporation of thesolvent or solvent mixture employed in preparing the coating mixture.The usual fillers such as calcene, aluminum silicate powder, etc. may beadded in an amount ranging from 10 to 100 parts by weight per 100 partsby Weight of the prepared polymer-resin-solvent mixture.

The cresolphenoland urea-formaldehyde resins which are mixed withpolysulfide polymer may be any one of the phenolic resins that arecurrently available on the market. As illustrative examples of suchphenolic resin, the following may be mentioned:

Phenolic oil soluble BR 3360 Superbeckacite 1001 Urea-formaldehyde resinBeetle 227-8 It is to be noted that the nature or character of thephenolic resin is immaterial so long as it contains a reactive methylol(-CHzOH) group on the phenol ring.

With phenolic resins and polysulfide polymers, the hydrogen is splitfrom the mercaptan (-SH) terminal of the polymer and hydroxyl from themethylol group of the resin to form a monosulfide linkage and water.With epoxy ether resins and polysulfide polymers, the hydrogen from themercaptan terminal of the polysulfide polymer is split and unites withthe epoxide to form a hydroxyl group. With polyamide resin andpolysulfide polymer it is believed that an esterification takes placewith the splitting out of water.

The polyamide resin which is mixed with the polysulfide polymer is aresinous product obtained by the condensation of a mixture of dimerizedand trimerized unsaturated fatty acids of vegetable oils includingdibasic and tribasic acids with diethylene, triamine. It ischaracterized by the general formula:

wherein R represents the aliphatic chain of the unsaturated fatty acidsand n represents a numeral ranging from 5 to 15, with an acid numberranging from 7 approximately to 85 approximately. The various grades ofthese resins, which are available on the market, and the methods ofpreparing them are Well known to the art and need not be discussedherein. In addition polyamide resins obtained by the condensation ofdibasic organic acids such as, malonic, maleic, fumaric, succinic,glutaric, a,m'-oxydiacetic, adipic, pirnelic, phthalic,tetrahydrophthalic, suberic, azelaic, sebacic, etc., with alkylaminessuch as ethylene diamine, triethylene tetramine and tetramethylenepentamine may also be employed.

The unsaturated fatty acids employed in preparing the dimers and trimersfor condensation with ethylene diamine or diethylene triamine are oleic,linolic, linoleic, linolinic, 'y-hexanoic, tetracrylic, etc., ormixtures thereof.

For purposes of the present invention we prefer to employ a polyamideresin having an average molecular weight of 3000-6500, a ball and ringsoftening point (A. S. T. M.) C. of 28 or 43 minimum, and viscosities(Gardner-Holdt) of A3-D which are determined as a 35% solution of theresin in a 1:1 mixture of butanol and toluene when mixed With apolysulfide polymer. In such mixture the proportions range from 70-75%of polysulfide polymer and 30-25% of polyamide resin.

The foregoing polyamide resins are sold on the market under the brandname designation #1008, #110, #938, #948 and #958, respectively.

The epoxy ether resins, commonly referred to as, polyglycidyl ethers ofpolyhidric alcohols and glycidyl ethers of bis-phenols, employed inaccordance with the present invention, are characterized by thefollowing general' formulae:

wherein R represents the divalent hydrocarbon radical of the dihydricphenol and n represents the extent of copolymerization as determined bythe epoxy equivalent which ranges from 140 to 4000. By the epoxyequivalency is meant the average number of 1,2-epoxy groups 0 Q l 1contained in the average molecule. It is expressed in the trade as thegrams of the polymeric material or resin containim one gram equivalentof epoxide.

The epoxy others are obtained by the procedures described in UnitedStates Patents 2,500,600; 2,633,458; 2,642,412; 2,324,483; 2,444,333;2,520,145; 2,521,911; all of Which are incorporated herein by referencefor examples of the types of epoxy ether resins that may be employed inadmixture with polysulfide polymers.

Of the several types with varying epoxide equivalents, We prefer toemploy the epoxy ether resin having an epoxide equivalent rangingbetween 190-210 and 225-290, preferably the former because of its lowmelting point, 8-12 C. (as determined by Durrans mercury method) andease of formulation with other components.

The proportion of epoxy ether resin may vary from 25 to 100 parts byweight per 25 to 100 parts by weight of a polysulfide polymer. To themixture are added from 1 to 20 parts by Weight of any one of the knownaliphatic or aromatic organic amines as disclosed in U. S. P. 2,500,600and 2,643,412, to cure the components. For direct, i. e. immediate,application to either sheet metal or fibrous material, 100 to 120 partsby Weight of aluminum silicate powder or other filler are added and themixture stirred. When the temperature of the mixture ranges from 16 to25 C., 3-6 parts by weight of the amine per parts of epoxy ether resinare added. When the temperature ranges between 25-40 C., 2-3 parts byweight of the amine per 100 parts of epoxy ether resin are added. In thecase where a lapse of time takes place, i. e. after mixing and prior tocoating-usually about 30 minutes-and the temperature ranges from 20 to30 C., 3-6 parts by weight of the amine per 100 parts of epoxy etherresin are added to the mixture.

In some instances it is desirable to incorporate into the bonding oradhesive mixture prior to the coating of the sheet metal, metal veneeror fibrous material, a filler. This filler appears to improve the bondbetween the sheet metal and fibrous base material. Such fillers may beone or a mixture of the following materials:

The following examples will show the preparation of some of theforegoing adhesive or bonding mixtures. It is to be clearly understoodthat they are merely illustrative and that the invention claimed is notto be limited thereto. All the parts given are by weight.

EXAMPLE I Epoxy ether resin (sold under the brand name of Epon 828 andhaving an epoxy equivalent of 190-210) 100 Polysulfide polymer (soldunder the name of Thiokol LP-33 having a molecular weight ofapproximately 1000 100 Aluminum silicate powder Diethylaminopropylamine6 The first two components are thoroughly mixed or blended at roomtemperature. To this mixture is added with stirring the aluminumsilicate powder until a uniform dispersion is obtained. Thediethylaminopropylamine is then added and the mixture stirred. again.

An aluminum foil of approximately 1/250 of an inch in thickness andapproximately 36 inches wide, which was coiled on a separate roll, waspassed on a roller of a conventional coating machine equipped with adoctor roll and the above coating applied from a coating roll to oneside of the foil to a thickness of 0.002 to 0.007 of an inch. A 15 lb.asphalt-felt, coiled on a separate roll, was placed in contact with thecoated side of the aluminum foil. After contact the felted-metal foilwas wound on a single shaft center-rewind. Intimate contact between thefelt and coated aluminum is obtained by means of the conventionalbreaking device providing tension on the roll coil containing thealuminum and on the roll coil containing the asphalted-felt.

Should the temperature during coating exceed 30 C.,. i

say between 30-40" C. a small mount of either toluene or xylol may beadded to the coating mixture as a thinner or diluent so as to retard thecuring of the bonding or adhesive mixture during the coating operation.

The felted side of approximately 36" square of the metal foil preparedas above was coated evenly with a cut-back asphalt of the type employedby roofers and allowed to remain for a period of 4-8 hours. After thattime there was no separation of the asphalted-felt from the adhesivelayer or bonding agent. This clearly established that while the volatilesolvents from the cutback asphalt penetrated the felt, there was noeffect on the bond or adhesive layer between the asphalted felt andmetal foil.

The uncoated aluminum side of a strip of approxi- Lmately 6" square ofthe felted-foil, prepared as above, was exposed to heat 'ofapproximately 400 C. from a blow torch placed at distance of 12 inchesfrom the foil for a period of 30 minutes. After the foil cooled toroomtemperattue, an attempt to pull or peel off the asphalted felt away fromthe adhesive or bonding layer, failed. The metal foil could be flexedand bent Without loosening or detaching the bonding ar adhesive layer.

The foil prepared as above is of value not only as a roofing materialbut also as a flashing and reflective insulation in sidewalls, underroof rafters, on ceilings, and beneath the floor in basementless homes.It may be used in place of building paper to protect againstrot-promoting moisture within the walls.

It may also be used on the roof of a building as a valley flashing, avent pipe flange, a chimney flashing and as an under flashing.

EXAMPLE II An aluminum foil of approximately of an inch in thickness andapproximately 36 inches wide was coated with the following composition:

Epoxy ether (sold under the brand name of Epon 1007 and having an epoxyequivalent The first two components were cooked at 500-520 F. for about2 hours and allowed to reach room temperature. The xylene and cobaltnaphthenate were then added.

To each gallon of the above cooled formulation, l-3 lbs. of finelypowdered metallic copper were added and the mixture stirred until auniform dispersion was obtained.

The finished coating composition was applied to the aluminum foil bymeans of lithographer roller and the coated foil passed along rollers toa heated oven, the internal temperature of which was approximately 300-800 F. and allowed to remain there for about 1-60 minutes. Thereafter,the coated foil was bonded to the fibrous material as in Example I andcrimped.

Instead of the above formulation which can be applied as an outsidecoating to the metallic foil prior to bonding or coating with theadhesive layer, we have found that the mixture of soya bean fatty acidsand dehydrated castor oil can be replaced by varying amounts ofureaformaldehyde resins, melamine-formaldehyde resins, orphenol-formaldehyde resins or mixtures thereof. When such replacementsare made the volatile solvent thinner may consist of 25 parts by weightof ketones, aromatic hydrocarbons, acetates, alcohols, ether alcohols,ether alcohol acetates, and the like. Compositions of this type readilycure within 1-60 minutes at 300550 F. or higher.

The foil as prepared above is of exceptional value as a flashingmaterial to the building trade. It is recognized that masonry Wallscannot be depended upon to be permanently waterproof, even though thebrick, stone, terracotta or other materials may be waterproof as a. unitand the mortar used may be rich enough to be considered waterproof. Theshrinkage of these materials and the natural movement of the buildingmay cause a masonry wall to leak. It is, therefore, highly desirable tohave the flashing so located as to prevent rain water or moisture thatmay enter the exterior wall from coming in contact with steel or woodmembers in the wall, and seeping into the side of the building.

There are several kinds of material that are used as flashing such asasphalt saturated felts, metal sheet bonded to asphalt felt by means ofasphalt or asphalt mastics, and sheet metals such as copper, aluminum,zinc, galvanized sheet metal, and the like. Flashing of this type oncebuilt into the wall cannot be replaced when worn or corroded withouttremendous replacement cost. The sheet metals, particularly aluminum,corrode in time because of the alkaline materials in the mortar, cement,etc.

The composition foil prepared according to Example II avoids the aboveshortcomings, since the outer coating is extremely resistant tocorrosive action and once installed is durable, prevents leaks, andsolves drainage and penetration problems.

EXAMPLE III Mixture A Polyamide resin (sold under the brand #1008 andhaving an average molecular weight of 3000-6500 The resin is dissolvedin the mixture of the solvents at room temperature until a clear liquidis obtained.

Mixture B Epoxy ether resin (sold under the brand name of Epon 864 andhaving an epoxy equivalent to 300-375) 20 Methyl ethyl ketone 10 Toluene10 The epoxy other is dissolved in the mixture of solvents at roomtemperature until a clear liquid is obtained. Mixtures A and B arecombined with stirring and 6 parts of diethylamin'opropylamine addedwhile stirring was continued. The solution was applied to the aluminumfoil and then contacted with a 15 lb. asphalted-felt. The bonded foilwas treated as in Example I.

The cure of the adhesive or bonding agent can be expedited by passingthe foil through the oven for 2 hours at 60 C. or for 5 to 15 minutes atC.

When the felted side of the bonded foil was coated with the cut-backasphalt, the same results as in Example I were obtained. The heating ofthe uncoated side of the aluminum, as in Example I, showed no cracking,no flowing and no detaching of the adhesive layer from either the metaland felt surfaces. The adhesive or bonding layer was elastic and as aconsequence the foil could be flexed and bent.

EXAMPLE IV Example I was repeated with the exception that the adhesiveor bonding mixture was replaced by the following:

The liquid phenolic thermosetting resin was mixed with the polysulfiidepolymer and 14 parts by weight of 2,4,6-tridimethylaminomethyl) phenoladded and the mixture applied as a coating. Instead of the above liquidphenolic thermosetting resin, we can also employ liquid phenolic resinsavailable under the brand names of BL3128, BZ9700, XV 17656, Plyophen5010, etc. All of these phenolics contain a methylol group and as aconsequence reactive with the other components of the adhesive orbonding mixture.

EXAMPLE V Example I was repeated with the exception that the aluminumfoil and 15 lb. asphalted-felt were replaced by an aluminum foil of0.008 in thickness and woven asbestos fabric having a thickness of about4 of an inch.

EXAMPLE VI Example I was again repeated with the exception that theasphalted-felt was replaced by kraft paper having a thickness of A of aninch. In this coating application, it was found that the adhesive orbonding agent did not completely saturate the paper and that a definitefilm of the bonding agent can be observed between the kraft paper andsheet metal.

The only precaution to be observed in the practice of this invention isthat when outer coating such as in Example II is to be applied to thesheet metal or metal veneer, it is desirable that such coating beapplied first, followed by the application of the adhesive or bondingagent to a fibrous material. The reason for this is that since theoutside coating must be heated while in the oven to accelerate thecuring of the coating composition, there is likelihood that the fibrousmaterial, such as paper, cardboard, fabric, felt, canvas, and the like,may be adversely affected.

As may be noted from the foregoing description it is immaterial whetherthe sheet metal or the fibrous material are coated with the adhesive orbonding agents employed in accordance with the present invention, thechoice being left to the discretion of the operator of the coatingmachine.

Instead of employing the polyamides obtained by con- (lensing a mixtureof dimerized and trimerized unsaturated fatty acids including dibasicand tribasic acids with diethylene triamine, polyamides, obtained by thecondensation of dimerized and trimerized unsaturated fatty acids withethylenediamine may also be used. Such polymers are characterized by thegeneral formula:

wherein R represents the aliphatic chain of the unsaturated fatty acidsand n represents a numeral ranging from 5 to 15, with molecular weightsof 3000 to 9000. Various grades of these resins are available on themarket, and the methods of preparing them are well known to the art andneed not be repeated herein.

We may also employ a mixture of two polyamide resins of differentviscosities and of different average molecular weight. In such case, amixture consisting of -40% of a polyamide resin having a viscosity of Cmaximum (Gardner-Holdt); 30-20% of a polyamide resin having a viscosityof B-D (Gardner-Holdt) and an average molecular weight of 6000-9000;30-20% of a polyamide resin having a viscosity of A, C (Gardner-Holclt)and an average molecular weight of 3000-6500, and 30-20% of a polyamideresin having a viscosity of A3-Al (Gardner- Holdt) and an averagemolecular weight of 3000-6500 per 100 parts of such mixture, 10-20 partsof plasticizer, such as tricresol phosphate and the like, may be addedto impart flexibility to the resin mixture after curing. Instead ofplasticizers one part by weight of a saturated solution 10 of asynthetic or natural rubber may be incorporated per one part by weightof the mixed polyamide resin. To such mixtures from 1-15 parts by weightof any of the aforementioned aliphatic organic amines may be employed ascuring agent.

The mixture of polyamide resins of different viscosities may bedissolved together in a 1:1 mixture of isopropanol and toluene, mixturescontaining 30, 50 or 70% of toluene and 70, 50 or 30% of isopropanol mayalso be employed.

We have also found that by replacing the polysulfide polymer of theepoxy ether resin mixture by an equivalent amount of a solution ofnatural or synthetic rubber, chlorinated rubber, depolymerized rubber,neoprene, butadiene-acrylonitrile copolymer, butadiene-styrene copolymerand the like. Such rubber solutions, in. appropriate solvents normallyused to dissolve such rubbers, may be employed in lieu of thepolysulfide polymers in all of the foregoing adhesive or bonding mixturecompositions.

It is to be clearly understood that by the term polysulfide polymer asemployed in the appended claims, we include the polysulfide polymerscharacterized by the general formula and having molecular weightsranging from 500 to approximately 4000, the polyhydroxy polythiopolymers disclosed in U. S. P. 2,527,375, and the polythiopolymercaptanshaving a molecular weight of about 5,000-12,000. Similarly, by the termphenolic resin we include only the phenolic resins or phenoliccondensation products disclosed herein and their obvious equivalents.

While we have herein disclosed the preferred embodiments of ourinvention, we do not thereby desire or intend to limit ourselves solelyto the foreging specific examples, since it will be readily apparent tothose skilled in the art that the precise proportions of the materials rutilized in the preparation of the adhesive or bonding composition maybe varied and other materials having equivalent chemical or physicalproperties may be employed, if desired, within the spirit and scopethereof, and therefore, such limitations should be imposed as they areindicated in the appended claims.

We claim:

1. A laminated article of manufacture comprising a self-supporting sheetof asphalt-impregnated. fibrous material and a metallic sheet adheredthereto by a mixture of a bonding agent comprising 25 to parts by weightof a polysulfide polymer which is a mobile liquid at 25 C., having amolecular Weight of 500 to 12,000 and having the following structure:

wherein m represents a positive integer of from 3 to 23, 25 to 100 partsby weight of a glycidyl polyether of a polyhydric phenol having an epoxyequivalent of from to 4000.

2. A laminated article of manufatcure according to claim 1 wherein thepolysulfide polymer has a molecular weight of approximately 1000.

3. A laminated article of manufacture according to claim 1 but whereinthe glycidyl polyether of a polyhydric phenol has an epoxy equivalent of-210.

4. A laminated article of manufacture according to claim 1 but whereinthe metallic sheet is aluminum.

5. A laminated article of manufacture according to claim 1 but whereinthe fibrous material is 15 lb. asphalt felt.

6. A laminated article of manufacture according to claim 1 but whereinthe metallic sheet adhered to the sheet of fibrous material is crimped.

References Cited in the file of this patent UNITED STATES PATENTS1,996,951 Clark et al. Apr. 9, 1935 (Other references on following page)11 12 UNITED STATES PATENTS 7 Technical Service Bulletin #103, pamphletby Thiokol 2,466,963 Patrick et a1 Apt 12,1949 P- n New y, of June 9 p gs 14, 2,469,141 Alexander May 3, 1949 Thlollol 2 618 Watkins 25 1952Thlokol L1qu1d Polymer LP2, pamphlet by Thlokol 5 Corp., Trenton, NewJersey, of Febuary 24, 1948, pages OTHER REFERENCES 15 and 7 PolysulfideLiquid Polymers, article by J. S. Iorczak et al., reprint from Ind. &Eng. Chem, vol. 43, page 324-328, February 1951.

1.A LAMINATED ARTICLE OF MANUFACTURE COMPRISING A SELF-SUPPORTING SHEETOF ASPHALT-IMPREGNATED FIBROUS MATERIAL AND A METALLIC SHEET ADHEREDTHERETO BY A MIXTURE OF A BONDING AGENT COMPRISING 25 TO 100 PARTS BYWEIGHT OF A POLYSULFIDE POLYMER WHICH IS A MOBILE LIQUID AT 25* C.,HAVING A MOLECULAR WEIGHT OF 500 TO 12,000 AND HAVING THE FOLLOWINGSTRUCTURE: